Light-emitting device having a plurality of concentric light transmitting areas

ABSTRACT

The light-emitting device of the present invention includes LED chips provided on a ceramic substrate and a sealing material in which the LED chips are embedded. The sealing material contains a fluorescent substance and divided into a first fluorescent-substance-containing resin layer and a second fluorescent-substance-containing resin layer by a first resin ring and a second resin ring.

This application is a continuation of U.S. application Ser. No.12/942,327, filed Nov. 9, 2011, now allowed, which claims priority under35 U.S.C. §119(a) of Patent Application No. 2009-260123 filed in Japanon Nov. 13, 2009, the entire contents of each of which are herebyincorporated by reference.

TECHNICAL FIELD

The present invention relates to a light-emitting device and a methodfor producing the light-emitting device.

BACKGROUND ART

In recent years, LEDs have been widely used as light sources oflight-emitting devices. In order to obtain white light by alight-emitting device including LEDs, a method can be employed in which,for example, (i) three types of LEDs (red LED, blue LED, and green LED)are used, or (ii) a blue LED is used as a light source for a yellowfluorescent substance. It is demanded that a light-emitting device iscapable of emitting white light with sufficient luminance. In view ofthis, a light-emitting device including a plurality of LED chips hasbeen commercialized.

Patent Literature 1 discloses a technique to improve efficiency ofextracting light from a whole device. Specifically, a plurality of LEDchips 520 are provided on a base substrate 510 in such a manner thatevery corner of each of the plurality of LED chips faces a corner of theadjacent one of the plurality of LED chips (see FIG. 20). With thearrangement, a distance between sides of adjacent ones of the pluralityof LED chips 520 can be increased without changing center positions ofrespective ones of the plurality of LED chips 520, as compared to aconfiguration in which the same number of the plurality of LED chips 520are arranged on the base substrate 510 in a matrix manner. This makes itpossible, without enlarging a size of the base substrate 510, to preventlight emitted by each of the plurality of LED chips 520 from beingabsorbed and confined by the adjacent LED chips 520. Accordingly,efficiency of extracting light of the whole device can be improved.

Moreover, Patent Literature 1 also discloses a technique to reduceunevenness of chromaticity by the use of a dome-shaped color convertingmember which is provided in such a manner that an air layer is providedbetween the color converting member and an optical member.

CITATION LIST Patent Literature 1

Japanese Patent Application Publication, Tokukai, No. 2007-116095(Publication Date: May 10, 2007)

SUMMARY OF INVENTION Technical Problem

However, the technique to reduce unevenness of chromaticity disclosed inPatent Literature 1 relates to a technique to reduce unevenness ofchromaticity of a whole light-emitting surface of a singlelight-emitting device, and Patent Literature 1 is totally silent about atechnique to prevent unevenness of chromaticities of respectivelight-emitting devices.

According to the conventional technique, unevenness of chromaticity of awhole light-emitting surface of a single light-emitting device can bereduced but unevenness of chromaticities of respective light-emittingdevices cannot be suppressed.

The present invention is accomplished for solving the problem, and itsmain object is to cheaply provide light-emitting devices whosechromaticities are not varied so much because the chromaticities areadjusted while producing the light-emitting devices.

Solution to Problem

In order to attain the object, a light-emitting device of the presentinvention includes: a plurality of light-emitting elements provided on asubstrate; and a sealing material in which the plurality oflight-emitting elements are embedded, the sealing material containing afluorescent substance and being divided into a plurality of areas by apartition wall. According to the configuration, the sealing material isdivided into the plurality of areas. This makes it possible to producethe light-emitting device by providing one of the sealing materials inone area and measuring a chromatic characteristic, and then providinganother one of the sealing materials in the other area based on themeasurement result. Accordingly, it is possible to provide thelight-emitting devices in which chromaticities are adjusted so thatunevenness of chromaticities among the light-emitting devices isreduced. Moreover, in producing the light-emitting devices, it ispossible to control the number of products to be discarded due tononconformity to a desired chromaticity, and whereby a unit price of theproduct can be suppressed. Accordingly, the light-emitting device can beprovided at low cost.

In order to attain the object, a method for producing a light-emittingdevice of the present invention includes the steps of: (a) providing aplurality of light-emitting elements on a substrate; (b) providing apartition wall on the substrate; (c) providing a first sealing materialcontaining a fluorescent substance in one of areas separated by thepartition wall; (d) measuring a chromatic characteristic of thelight-emitting device in which the first sealing material has beenprovided; (e) in accordance with a result of the measurement, providinga second sealing material containing a fluorescent substance in otherone of the areas separated by the partition wall; and (f) measuring thechromatic characteristic of the light-emitting device in which thesecond sealing material has been provided.

According to the configuration, the step of measuring a chromaticcharacteristic of the light-emitting device in which the first sealingmaterial has been provided and the step of providing the second sealingmaterial in accordance with the measurement result are separated. Thismakes it possible to closely adjust a chromaticity in producing thelight-emitting device. Accordingly, it is possible to control the numberof products to be discarded due to nonconformity to a desiredchromaticity, and whereby a unit price of the product can be suppressed.This makes it possible to easily produce the light-emitting devices atlow cost among which unevenness of chromaticities of the light-emittingdevices is reduced.

Advantageous Effects of Invention

The light-emitting device of the present invention includes: a pluralityof light-emitting elements provided on a substrate; and a sealingmaterial in which the plurality of light-emitting elements are embedded,the sealing material containing a fluorescent substance and beingdivided into a plurality of areas by a partition wall.

According to the configuration, the sealing materials are separated intoa plurality of areas. Accordingly, it is possible that one of thesealing materials is provided in one of the plurality of areas and achromatic characteristic is measured, and then the other one of thesealing materials is provided in the other one of the plurality of areasin accordance with the measurement result. Further, it is possible to(i) adjust a chromaticity, (ii) reduce unevenness of chromaticitiesamong the light-emitting devices, and (ii) provide the light-emittingdevice at low cost.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a top view illustrating a light-emitting device of Embodiment1.

FIG. 2 is a top view illustrating a wiring pattern of the light-emittingdevice of Embodiment 1.

FIG. 3 is a top view illustrating an arrangement of LED chips in thelight-emitting device of Embodiment 1.

FIG. 4 is a top view illustrating areas in which the LED chips arearranged in the light-emitting device of Embodiment 1.

FIG. 5 is a top view illustrating a configuration in a first measurementof the light-emitting device of Embodiment 1.

FIG. 6 is a top view illustrating a configuration in a secondmeasurement of the light-emitting device of Embodiment 1.

FIG. 7 is a cross-sectional view taken along the line X-X′ of FIG. 1.

FIG. 8 is a graph illustrating chromaticity coordinates of CIE.

FIG. 9 is a top view illustrating a light-emitting device of Embodiment2.

FIG. 10 is a top view illustrating a wiring pattern of thelight-emitting device of Embodiment 2.

FIG. 11 is a top view illustrating an arrangement of LED chips in thelight-emitting device of Embodiment 2.

FIG. 12 is a top view illustrating a configuration in a firstmeasurement of the light-emitting device of Embodiment 2.

FIG. 13 is a top view illustrating an arrangement of the LED chips inthe light-emitting device of Embodiment 2.

FIG. 14 is a top view illustrating a configuration in a secondmeasurement of the light-emitting device of Embodiment 2.

FIG. 15 is a graph illustrating chromaticity coordinates of CIE.

FIG. 16 is a top view illustrating a light-emitting device of Embodiment3.

FIG. 17 is a top view illustrating a configuration in a firstmeasurement of a light-emitting device of Embodiment 4.

FIG. 18 is a top view illustrating a configuration in a secondmeasurement of a light-emitting device of Embodiment 5.

FIG. 19 is a top view illustrating a configuration of a light-emittingdevice of Embodiment 6.

FIG. 20 is a view schematically illustrating an arrangement of LED chipsof a conventional technique.

DESCRIPTION OF EMBODIMENTS Embodiment 1

The following describes an embodiment of the present invention withreference to FIGS. 1 through 7.

[Configuration of Light-Emitting Device 100]

FIG. 1 is a top view illustrating a configuration example of alight-emitting device 100 (light-emitting device) of the presentembodiment.

As shown in FIG. 1, the light-emitting device 100 includes a ceramicsubstrate 10 (substrate), a patterned electrode wire 15 (patternedwire), LED chips 60 (light-emitting elements), a firstfluorescent-substance-containing resin layer 40 (sealing material, firstsealing material), a second fluorescent-substance-containing resin layer50 (sealing material, second sealing material), a first resin ring 20(partition wall), and a second resin ring 30 (partition wall).

FIG. 2 is a top view illustrating a configuration in which the ceramicsubstrate 10 is provided with the patterned electrode wire 15, anelectrode land (anode) 90, an electrode land (cathode) 95, and a printedresistance element 80. FIG. 3 is a top view illustrating a configurationin which the LED chips 60 are connected to the patterned electrode wire15 via wires 70. FIG. 5 is a top view illustrating a configuration inwhich the first fluorescent-substance-containing resin layer 40 isprovided in a first area 110 (area). FIG. 6 is a view illustrating aconfiguration in which the second fluorescent-substance-containing resinlayer 50 is provided in a second area 120 (area). FIG. 7 is across-sectional view taken along the line X-X′ of FIG. 1.

(Ceramic Substrate 10)

The ceramic substrate 10 is a substrate on which the LED chips 60, etc.are provided. As shown in FIG. 1, the electrode land (anode) 90, theelectrode land (cathode) 95, and the printed resistance element 80 areprovided on the ceramic substrate 10. Moreover, the ceramic substrate 10has holes 97 for mounting a substrate.

According to the present embodiment, the ceramic substrate 10 has arectangular shape of 12 mm×15 mm with a thickness of 1 mm. Note that ashape of the substrate included in the light-emitting device of thepresent invention is not limited to this. In the present embodiment,each of the holes 97 for mounting a substrate is a circular hole havinga diameter of 1.4 mm and two of the holes 97 for mounting a substrateare provided at opposing corners of the ceramic substrate 10 so that thelight-emitting device 100 can be fixed. Note that, in a case where ahole for mounting a substrate is formed in a substrate included in thelight-emitting device of the present invention, a diameter of the holeis not limited to the above described diameter.

Note that, even though the ceramic substrate 10 is used in the presentembodiment, a material of the substrate is not limited to ceramic. Forexample, it is possible to use a metal substrate having a surface onwhich an insulating layer is provided.

(Patterned Electrode Wire 15)

As shown in FIG. 2, the patterned electrode wire 15 is a patterned Auelectrode which is provided on the main surface of the ceramic substrate10 and has a width of 300 μm and a thickness of 10 μm. The patternedelectrode wire 15 is connected with the electrode land (anode) 90, theelectrode land (cathode) 95, and the printed resistance element 80. Eachof the electrode land (anode) 90 and the electrode land (cathode) 95 (i)is made of Ag—Pt, (ii) has a thickness of 20 μm, and (iii) has a shapemade up of a rectangular part and two half round parts having diametersof 1.4 mm between which the rectangular part is provided. Therectangular part has sides of 2 mm and 1.4 mm, which sides of 1.4 mmcorrespond to the respective diameters of the round parts. Note that, ina case where an electrode land is provided on a substrate included inthe light-emitting device of the present invention, a shape and a sizeof the electrode land are not limited to those described above.

Moreover, the patterned electrode wire 15 connects anode-side electrodesof the LED chips 60 to the electrode land (anode) 90. The electrode land(anode) 90 is disposed in an edge area of the main surface of theceramic substrate 10. Moreover, the patterned electrode wire 15 connectscathode-side electrodes of the LED chips 60 to the electrode land(cathode) 95 provided on the ceramic substrate 10. The electrode land(cathode) 95 is provided in an edge area opposite to the edge area inwhich the electrode land (anode) 90 is provided.

(Printed Resistance Element 80)

The printed resistance element 80 is not limited in particular in termsof its shape and material. In the present embodiment, the printedresistance element 80 is made of ruthenium oxide RuO₂ and has a width of300 μm, a thickness of 10 μm, and a resistance of 1 M. Moreover, theprinted resistance element 80 is also not limited in terms of its color.In the present embodiment, the printed resistance element 80 is black.Note that the light-emitting device of the present invention can includea protective element instead of or in addition to the printed resistanceelement.

(LED Chip 60)

As shown in FIG. 3, the LED chips 60 are connected to the patternedelectrode wire 15 via the wires 70. On the main surface of the ceramicsubstrate 10, 21 pieces of the LED chips 60 are provided in the firstarea 110 and 6 pieces of the LED chips 60 are provided in the secondarea 120. In the present embodiment, each of the LED chips 60 has awidth of 240 μm, a length of 400 μm, and a height of 80 μm. Note thatthe first area 110 is an area between the first resin ring 20 and thesecond resin ring 30. The second area 120 is an area inside the secondresin ring 30.

As shown in FIG. 4, the area in which the LED chips 60 are provided isdivided in to three areas by the patterned electrode wire 15. A firstelectric area 16 encompasses 9 pieces among the LED chips 60 provided inthe first area 110. A second electric area 17 encompasses 3 pieces amongthe LED chips 60 provided in the first area 110 and 6 pieces among theLED chips 60 provided in the second area 120. A third electric area 18encompasses 9 pieces among the LED chips 60 provided in the first area110.

(First Resin Ring 20 and Second Resin Ring 30)

As shown in FIG. 5, the first resin ring 20 and the second resin ring 30separate, into areas, fluorescent-substance-containing resins which aresealing materials covering the LED chips 60. In the present embodiment,the first resin ring 20 and the second resin ring 30 separates the firstarea 110 and the second area 120.

Each of the first resin ring 20 and the second resin ring 30 is aring-shaped member made of a white silicon resin which contains titanicoxide TiO₂ as a filler. Alternatively, each of the first resin ring 20and the second resin ring 30 can be a ring-shaped member to which whitesolder mask is applied. Note that the filler used in the first resinring 20 and the second resin ring 30 is not limited to the titanic oxideTiO₂. Moreover, the first resin ring 20 and the second resin ring 30serve to hold shapes of the first fluorescent-substance-containing resinlayer 40 and the second fluorescent-substance-containing resin layer 50by damming the fluorescent-substance-containing resin poured into thefirst area 110 and the second area 120 in producing the firstfluorescent-substance-containing resin layer 40 and the secondfluorescent-substance-containing resin layer 50. That is, the first area110 is an area in which the first fluorescent-substance-containing resinlayer 40 is provided, and the second area 120 is an area in which thesecond fluorescent-substance-containing resin layer 50 is provided.

Note that, in the present embodiment, colors of the silicon resin andthe solder mask are white which are used in each of the first resin ring20 and the second resin ring 30. However, the color is not limited towhite but can be milky white.

In the present embodiment, the first resin ring 20 has a circular shapewith a ring width of 0.5 mm and a ring diameter of 8.6 mm. The secondresin ring 30 has a circular shape with a ring width of 0.5 mm and aring diameter of 3.9 mm. In the present embodiment, the first resin ring20 and the second resin ring 30 are concentrically arranged. Note that,in the present embodiment, the first resin ring 20 and the second resinring 30 having circular shapes are discussed. However, the first resinring 20 and the second resin ring 30 can be a cyclic polygon.

Note that it is preferable that each of the first resin ring 20 and thesecond resin ring 30 includes at least one of a thickener and adiffusing agent.

(First Fluorescent-Substance-Containing Resin Layer 40 and SecondFluorescent-Substance-Containing Resin Layer 50)

As shown in FIGS. 5 and 6, the first fluorescent-substance-containingresin layer 40 and the second fluorescent-substance-containing resinlayer 50 are formed by filling the fluorescent-substance-containingresin which is the sealing material covering the LED chips 60.

Note that each of the first fluorescent-substance-containing resin layer40 and the second fluorescent-substance-containing resin layer 50 cancontain a plurality of fluorescent substances. Moreover, at least one ofan amount and a composition of the fluorescent substance contained inthe first fluorescent-substance-containing resin layer 40 can bedifferent from that of the fluorescent substance contained in the secondfluorescent-substance-containing resin layer 50. In the presentembodiment, each of the first fluorescent-substance-containing resinlayer 40 and the second fluorescent-substance-containing resin layer 50contains a green fluorescent substance of Ca₃(Sr.Mg)₂Si₃O₁₂:Ce, and ared fluorescent substance of (Sr.Ca)AlSiN₃:Eu. Note that the type of thefluorescent substance is not limited in particular.

In the present embodiment, only a single firstfluorescent-substance-containing resin layer 40 having a circular shapeis provided for example. However, the number of the fluorescentsubstance containing resin layer is not limited to this, but a pluralityof circular fluorescent substance containing resin layers can beprovided concentrically. A light-emitting device having such aconfiguration can be suitably used as (i) a light source of anilluminating device having a circular shape with respect to its lightemitting face, or (ii) a light source of an illuminating device whichneeds to be optically connected with an external optical componentappropriately. The illuminating device having a circular shape withrespect to its light emitting face can be, for example, a bulb-typeilluminating device. Moreover, the illuminating device which needs to beoptically connected with an external optical component appropriately canbe, for example, an illuminating device which is provided with anexternal lens for adjusting a light distribution characteristic whichexternal lens is provided directly above the illuminating device.

[Method for Producing Light-Emitting Device 100]

A method for producing the light-emitting device 100 of the presentembodiment includes the steps of: providing the plurality of LED chips60 on the ceramic substrate 10; providing the first resin ring 20 andthe second resin ring 30 on the ceramic substrate 10 on which theplurality of LED chips 60 have been provided; providing the firstfluorescent-substance-containing resin layer 40 containing a firstfluorescent substance in the first area 110 which is provided betweenthe first resin ring 20 and the second resin ring 30; measuring achromatic characteristic of the light-emitting device 100 in which thefirst fluorescent-substance-containing resin layer 40 has been provided;providing the second fluorescent-substance-containing resin layer 50, inaccordance with the measurement result, in the second area 120 which isseparated by the second resin ring 30; and measuring a chromaticcharacteristic of the light-emitting device 100 in which the secondfluorescent-substance-containing resin layer 50 has been provided.

(Arrangement of LED Chips 60)

First, as shown in FIG. 3, the plurality of LED chips 60 are provided onthe ceramic substrate 10 in such a manner that the plurality of LEDchips 60 are arranged on a circle concentric with the first resin ring20 and the second resin ring 30. The plurality of LED chips 60 are fixedby silicon resin. Then the plurality of LED chips 60 are wire-bondedwith the patterned electrode wire 15 via the wires 70.

(Providing First Resin Ring 20 and Second Resin Ring 30)

As shown in FIG. 5, the first resin ring 20 and the second resin ring30, which are partition walls, are provided on the ceramic substrate 10on which the plurality of LED chips 60 have been provided.

The first resin ring 20 and the second resin ring 30 can be formed withthe use of a dispenser. In the present embodiment, the first resin ring20 and the second resin ring 30 are cured at a temperature of 150degrees for 60 minutes. Note that the curing temperature and the curingtime are not limited to those described above.

It is preferable that the first resin ring 20 and the second resin ring30 are provided so as to partially cover the patterned electrode wire 15and the wires 70. In the present embodiment, the plurality of LED chips60 are provided and wire-bonded, and then the first resin ring 20 andthe second resin ring 30 are provided. However, it is possible that thefirst resin ring 20 and the second resin ring 30 are provided first, andthen the plurality of LED chips 60 are provided and wire-bonded.

(Providing First Fluorescent-Substance-Containing Resin Layer 40)

As shown in FIG. 5, the first fluorescent-substance-containing resinlayer 40 containing a first fluorescent substance is provided in thefirst area 110 which is an area separated by the first resin ring 20 andthe second resin ring 30.

FIG. 8 is a graph illustrating chromaticity coordinates of CIE. (a) inFIG. 8 indicates a chromaticity range after the firstfluorescent-substance-containing resin layer 40 is provided, and (b) inFIG. 8 indicates a chromaticity range after the secondfluorescent-substance-containing resin layer 50 is provided.

The first fluorescent-substance-containing resin layer 40 is formed byfilling the first area 110 with a mixture of the first fluorescentsubstance and a silicon resin which is a sealing material so that lightcan be emitted at (x, y)=(0.32, 0.285) of chromaticity coordinates ofCIE in FIG. 8. In the present embodiment, the firstfluorescent-substance-containing resin layer 40 is formed at a curingtemperature of 150 degrees for 30 minutes. Note that the curingtemperature and the curing time are not limited to those describedabove.

(First Measurement)

A chromatic characteristic of the light-emitting device 100 in which thefirst fluorescent-substance-containing resin layer 40 has been providedis measured. The first measurement of a chromatic characteristic iscarried out by, for example, causing the 21 pieces of the LED chips 60provided in the first area 110 and the 6 pieces of the LED chips 60provided in the second area 120 to emit light.

The measured chromaticity range of the firstfluorescent-substance-containing resin layer 40 is indicated by (a) inFIG. 8.

(Providing Second Fluorescent-Substance-Containing Resin Layer 50)

In accordance with the measurement result, the secondfluorescent-substance-containing resin layer 50 containing a secondfluorescent substance is provided in the second area 120 which is anarea inside the second resin ring 30 (see FIG. 6).

The recitation “in accordance with the measurement result” means that anamount and a composition of a fluorescent substance to be contained in aresin which constitutes the second fluorescent-substance-containingresin layer 50 are determined in accordance with the chromaticcharacteristic of the light-emitting device 100 measured in the firstmeasurement, and the second fluorescent-substance-containing resin layer50 is provided so that a desired chromatic characteristic of thelight-emitting device 100 can be obtained.

The second fluorescent-substance-containing resin layer 50 is formed byfilling the second area 120 with a mixture of the second fluorescentsubstance and a silicon resin which is a sealing material so that thelight-emitting device 100 emits light at (x, y)=(0.455, 0.415) in thechromaticity coordinates of CIE. In the present embodiment, the secondfluorescent-substance-containing resin layer 50 is formed at a curingtemperature of 150 degrees for 5 hours. Note that the curing temperatureand the curing time are not limited to those described above.

The second fluorescent-substance-containing resin layer 50 can have ahemispherical shape which is upwardly convexed.

(Second Measurement)

A chromatic characteristic of the light-emitting device 100 in which thesecond fluorescent-substance-containing resin layer 50 has been providedis measured. The second measurement of a chromatic characteristic iscarried out by, for example, causing the 21 pieces of the LED chips 60provided in the first area 110 and the 6 pieces of the LED chips 60provided in the second area 120 to emit light. The measured chromaticityrange is indicated by (b) in FIG. 8.

In the light-emitting device 100, the printed resistance element 80 isprovided under the first resin ring 20. This makes it possible tofurther suppress absorption of light by the printed resistance element80. Moreover, the first resin ring 20 protects an upper face (surface,etc) of the printed resistance element 80. Further, according to theconfiguration, a size of the light-emitting device 100 can be downsizedeven though the printed resistance element 80 is provided.

Note that, in the present embodiment, only a single firstfluorescent-substance-containing resin layer 40 having a circular shapeis provided for example. However, the number of thefluorescent-substance-containing resin layer is not limited to this, buta plurality of circular fluorescent-substance-containing resin layerscan be provided concentrically. The light-emitting device having such aconfiguration can be suitably used as (i) a light source of anilluminating device, (e.g., a bulb-type illuminating device) having acircular shape with respect to its light emitting face or (ii) a lightsource of an illuminating device which needs to be appropriatelyoptically-connected with an external optical component whichilluminating device is provided with an external lens for adjusting alight distribution characteristic which external lens is provideddirectly above the illuminating device.

Embodiment 2

The following describes another embodiment of the present invention withreference to FIGS. 9 through 15. Note that, for convenience ofexplanation, the like numerals are given to components having functionssimilar to those in Embodiment 1, and explanations of the components areomitted. In the present embodiment, differences from Embodiment 1 aremainly discussed.

[Configuration of Light-Emitting Device 200]

FIG. 9 is a top view illustrating a configuration example of alight-emitting device 200 of the present embodiment. As shown in FIG. 9,the light-emitting device 200 has the same configuration as thelight-emitting device 100 of Embodiment 1 except that the light-emittingdevice 200 includes a ceramic substrate 12 instead of the ceramicsubstrate 10.

FIG. 10 is a top view illustrating a configuration in which the ceramicsubstrate 12 is provided with a patterned electrode wire 15, anelectrode land (anode) 90, an electrode land (cathode) 95, and a printedresistance element 80. FIG. 11 is a top view illustrating aconfiguration in which LED chips 60 in a first area 110 are connected toa patterned electrode wire 15 via wires 70. FIG. 12 is a top viewillustrating a configuration in which a firstfluorescent-substance-containing resin layer 40 is provided in the firstarea 110. FIG. 13 is a top view illustrating a configuration in whichLED chips 60 in a second area 120 are connected to the patternedelectrode wire 15 via wires 70. FIG. 14 is a top view illustrating aconfiguration in which a second fluorescent-substance-containing resinlayer 50 is provided in the second area 120.

(Ceramic Substrate 12)

The ceramic substrate 12 has the same configuration as the ceramicsubstrate 10 of Embodiment 1 except that a thickness of the ceramicsubstrate 12 is 0.8 mm.

[Production Method of Light-Emitting Device 200]

In a method for producing the light-emitting device 200 of the presentembodiment, the LED chips 60 are provided in the second area 120 aftermeasuring a chromatic characteristic of the light-emitting device 200 inwhich the first fluorescent-substance-containing resin layer 40 has beenprovided, unlike the production method of Embodiment 1 in which the LEDchips 60 are provided in the second area 120 before measuring achromatic characteristic of the light-emitting device 100 in which thefirst fluorescent-substance-containing resin layer 40 has been provided.

(Providing LED Chips 60 in First Area 110)

As shown in FIG. 11, the LED chips 60 are provided in the first area 110on the ceramic substrate 12 of FIG. 10 in which the patterned electrodewire 15, the electrode land (anode) 90, the electrode land (cathode) 95,and the printed resistance element 80 are provided. As shown in FIG. 11,21 pieces of the LED chips 60 are provided in the first area 110 on amain surface of the ceramic substrate 12 and fixed by silicon resin.

(Providing of Resin Ring)

A first resin ring 20 and a second resin ring 30 are provided.

(Providing of First Fluorescent-Substance-Containing Resin Layer 40)

Then, the first fluorescent-substance-containing resin layer 40 isprovided in the first area 110.

As shown in FIG. 12, the first fluorescent-substance-containing resinlayer 40 containing a first fluorescent substance is provided in thefirst area 110 which is an area between the first resin ring 20 and thesecond resin ring 30.

FIG. 15 is a graph illustrating chromaticity coordinates of CIE. (a) inFIG. 15 indicates a chromaticity range after the firstfluorescent-substance-containing resin layer 40 is provided, and (b) inFIG. 15 indicates a chromaticity range after the secondfluorescent-substance-containing resin layer 50 is provided.

The first fluorescent-substance-containing resin layer 40 is formed byfilling the first area 110 with a mixture of the first fluorescentsubstance and a silicon resin which is a sealing material so that lightcan be emitted at (x, y)=(0.427, 0.395) of the chromaticity coordinatesof CIE in FIG. 15. In the present embodiment, the firstfluorescent-substance-containing resin layer 40 is formed at a curingtemperature of 150 degrees for 30 minutes. Note that the curingtemperature and the curing time are not limited to those describedabove.

(First Measurement)

A chromatic characteristic of the light-emitting device 200 in which thefirst fluorescent-substance-containing resin layer 40 has been providedis measured. The first measurement of a chromatic characteristic iscarried out by, for example, causing the 21 pieces of the LED chips 60provided in the first area 110 to emit light.

The measured chromaticity range of the firstfluorescent-substance-containing resin layer 40 is indicated by (a) inFIG. 15.

(Providing LED chips 60 in Second Area 120)

Then, as shown in FIG. 13, the LED chips 60 are provided in the secondarea 120. 6 pieces of the LED chips 60 are provided in the second area120 on the main surface of the ceramic substrate 12 and fixed by siliconresin.

(Providing Second Fluorescent-Substance-Containing Resin Layer 50)

Subsequently, in accordance with the measurement result, the secondfluorescent-substance-containing resin layer 50 is provided in thesecond area 120 (see FIG. 14). The secondfluorescent-substance-containing resin layer 50 is formed by filling thesecond area 120 with a mixture of the second fluorescent substance and asilicon resin which is a sealing material so that light can be emittedat (x, y)=(0.455, 0.415) of the chromaticity coordinates of CIE. Acuring temperature and a curing time for forming the secondfluorescent-substance-containing resin layer 50 are not limited inparticular. However, it is preferable that, for example, the curingtemperature is 150 degrees and the curing time is 5 hours.

(Second Measurement)

A chromatic characteristic of the light-emitting device 200 in which thesecond fluorescent-substance-containing resin layer 50 has been providedis measured. The second measurement of the chromatic characteristic iscarried out by, for example, causing the 21 pieces of the LED chips 60provided in the first area 110 and the 6 pieces of the LED chips 60provided in the second area 120 to emit light. The measured chromaticityrange is indicated by (b) in FIG. 15.

Embodiment 3

The following describes another embodiment of the present invention withreference to FIG. 16. Note that, for convenience of explanation, thelike numerals are given to components having functions similar to thosein Embodiment 1, and explanations of the components are omitted. In thepresent embodiment, differences from Embodiment 1 are mainly discussed.

[Configuration of Light-Emitting Device 250]

As shown in FIG. 16, the light-emitting device 250 has the sameconfiguration as the light-emitting device 100 of Embodiment 1 exceptthat the light-emitting device 250 includes a printed resistance element85.

(Printed Resistance Element 85)

As shown in FIG. 16, the printed resistance element 85 has almost thesame configuration as the printed resistance element 80 of Embodiment 1except that the printed resistance element 85 is provided between theceramic substrate 10 and the first resin ring 20, and the first resinring 20 wholly covers the printed resistance element 85.

[Method for Producing Light-Emitting Device 250]

The light-emitting device 250 of the present embodiment is produced bythe same way as that of Embodiment 1.

(First Measurement)

A chromatic characteristic of the light-emitting device 250 in which thefirst fluorescent-substance-containing resin layer 40 has been providedis measured. The first measurement of the chromatic characteristic iscarried out by, for example, causing the 21 pieces of the LED chips 60provided in the first area 110 and the 6 pieces of the LED chips 60provided in the second area 120 to emit light.

(Second Measurement)

A chromatic characteristic of the light-emitting device 250 in which thesecond fluorescent-substance-containing resin layer 50 has been providedis measured. The second measurement of the chromatic characteristic iscarried out by, for example, causing the 21 pieces of the LED chips 60provided in the first area 110 and the 6 pieces of the LED chips 60provided in the second area 120 to emit light.

Embodiment 4

The following describes another embodiment of the present invention withreference to FIG. 17. Note that, for convenience of explanation, thelike numerals are given to components having functions similar to thosein Embodiment 1, and explanations of the components are omitted. In thepresent embodiment, differences from Embodiment 1 are mainly discussed.

[Configuration of Light-Emitting Device 300]

FIG. 17 is a top view illustrating a light-emitting device 300 in whicha first fluorescent-substance-containing resin layer 40 is provided inthe first area 110 and a light-shielding plate 310 is provided in thesecond area 120. With this configuration, a first measurement of achromatic characteristic is carried out. As shown in FIG. 17, thelight-emitting device 300 has the same configuration as thelight-emitting device 100 of Embodiment 1 except that the light-emittingdevice 300 includes the light-shielding plate 310.

(Light-Shielding Plate 310)

As shown in FIG. 17, the light-shielding plate 310 is provided so as towholly cover the second area 120.

(Method for Producing Light-Emitting Device 300)

In a method for producing the light-emitting device 300 of the presentembodiment, the light-shielding plate 310 is provided so as to cover thesecond area 120 before measuring a chromatic characteristic of thelight-emitting device 300 in which the firstfluorescent-substance-containing resin layer 40 has been provided,unlike the production method of Embodiment 1 in which a chromaticcharacteristic of the light-emitting device 100 is measured after thefirst fluorescent-substance-containing resin layer 40 is provided.

(Providing Light-Shielding Plate 310)

On the ceramic substrate 10, the LED chips 60 are provided, the firstresin ring 20 and the second resin ring 30 are provided, and the firstfluorescent-substance-containing resin layer 40 is provided. After that,as shown in FIG. 17, the light-shielding plate 310 is provided so as towholly cover the second area 120.

(First Measurement)

After the first fluorescent-substance-containing resin layer 40 and thelight-shielding plate 310 are provided, a chromatic characteristic ofthe light-emitting device 300 is measured. The first measurement of thechromatic characteristic of the light-emitting device 300 is carried outby, for example, causing the 21 pieces of the LED chips 60 provided inthe first area 110 and 6 pieces of the LED chips 60 provided in thesecond area 120 to emit light.

(Providing Second Fluorescent-Substance-Containing Resin Layer 50)

Then, the light-shielding plate 310 covering the second area 120 isremoved and a second fluorescent-substance-containing resin layer 50 isprovided in the second area 120.

(Second Measurement)

The chromatic characteristic of the light-emitting device 300 in whichthe second fluorescent-substance-containing resin layer 50 has beenprovided is measured. The second measurement of the chromaticcharacteristic of the light-emitting device 300 is carried out by, forexample, causing the 21 pieces of the LED chips 60 provided in the firstarea 110 and the 6 pieces of the LED chips 60 provided in the secondarea 120 to emit light.

Embodiment 5

The following describes another embodiment of the present invention withreference to FIG. 18. Note that, for convenience of explanation, thelike numerals are given to components having functions similar to thosein Embodiment 1, and explanations of the components are omitted. In thepresent embodiment, differences from Embodiment 1 are mainly discussed.

[Configuration of Light-Emitting Device 400]

FIG. 18 is a top view illustrating a light-emitting device 400 of thepresent embodiment. As shown in FIG. 18, the light-emitting device 400has the same configuration as the light-emitting device 100 ofEmbodiment 1 except that the light-emitting device 400 includes a pseudofluorescent sheet 350.

(Pseudo Fluorescent Sheet 350)

As shown in FIG. 18, the pseudo fluorescent sheet 350 is provided so asto cover the second area 120. The pseudo fluorescent sheet 350 is aresin sheet containing a fluorescent substance of predetermined amountand composition. Moreover, plural kinds of the pseudo fluorescent sheets350 are provided which have various amounts and compositions offluorescent substances. The pseudo fluorescent sheets 350 are used fordetermining a mixing amount and a composition of a fluorescent substancecontained in the second fluorescent-substance-containing resin layer 50used for adjusting a chromaticity.

(Method for Producing Light-emitting Device 400)

In a method for producing the light-emitting device 400 of the presentembodiment, (i) the pseudo fluorescent sheet 350 is provided so as tocover the second area 120 before providing the secondfluorescent-substance-containing resin layer 50, (ii) a chromaticcharacteristic of the light-emitting device 400 is measured, and then(iii) the second fluorescent-substance-containing resin layer 50 isprovided in accordance with the measurement result. This productionmethod is different from that of Embodiment 1 in which the chromaticcharacteristic of the light-emitting device 100 is measured after thesecond fluorescent-substance-containing resin layer 50 is provided.

(First Measurement)

After the first fluorescent-substance-containing resin layer 40 isprovided, a chromatic characteristic of the light-emitting device 400 ismeasured. The first measurement of the chromatic characteristic iscarried out by causing the 21 pieces of the LED chips 60 provided in thefirst area 110 and 6 pieces of the LED chips 60 provided in the secondarea 120 to emit light.

(Providing Pseudo Fluorescent Sheet 350)

Then, the pseudo fluorescent sheet 350 is provided so as to cover thesecond area 120.

(Second Measurement)

After the pseudo fluorescent sheet 350 is provided, a second measurementof the chromatic characteristic is carried out with the pseudofluorescent sheet 350. The second measurement is repeated with pseudofluorescent sheets 350 replaced one after another so as to select apseudo fluorescent sheet 350 with which a desired chromaticity, that is,(x, y)=(0.455, 0.415) can be obtained.

After that, the second fluorescent-substance-containing resin layer 50is formed by mixing a second fluorescent substance and a silicon resinwhich is a sealing material so that a chromaticity to be obtainedbecomes the same as the chromaticity obtained by the pseudo fluorescentsheet 350. This is how the light-emitting device 400 is produced.

Embodiment 6

The following describes another embodiment of the present invention withreference to FIG. 19. Note that, for convenience of explanation, thelike numerals are given to components having functions similar to thosein Embodiment 1, and explanations of the components are omitted. In thepresent embodiment, differences from Embodiment 1 are mainly discussed.

[Configuration of Light-Emitting Device 450]

FIG. 19 is a top view illustrating a configuration in which LED chips 60provided in the first area 110 and LED chips 60 provided in the secondarea 120 are connected to each other via a bridge electrode 99.

As shown in FIG. 19, the light-emitting device 450 has the sameconfiguration as the light-emitting device 100 of Embodiment 1 exceptthat the LED chips 60 are connected in series.

(Bridge Electrode 99)

The bridge electrode 99 connects, in series, (i) LED chips 60 connectedin series in the first area 110 and (ii) LED chips 60 connected inseries in the second area 120. Moreover, in the present embodiment, thebridge electrode 99 is narrower and thinner in a part traversing thesecond resin ring 30 than the other part of the bridge electrode 99, andboth ends of the bridge electrode 99 which ends are connected to wireshave circular shapes. With the configuration in which the bridgeelectrode 99 is formed to be narrower and thinner in the part traversingthe second resin ring 30 than the other part of the bridge electrode 99,it is possible to prevent a problem that the firstfluorescent-substance-containing resin layer 40 and the secondfluorescent-substance-containing resin layer 50 are not separated intoareas and are mixed together. That is, in a case where the bridgeelectrode 99 does not have the shape described above, it may occur thatthe bridge electrode 99 which is provided between the second resin ring30 and the ceramic substrate 10 causes a gap therebetween, andaccordingly the first fluorescent-substance-containing resin layer 40and the second fluorescent-substance-containing resin layer 50 are notseparated into areas and are mixed together. Note that the shape of thebridge electrode 99 is not limited to the shape described above.

(Providing LED Chips 60)

An end part of an electrode land 95 which end part is disposed in thefirst area 110 is connected to an electrode of a LED chip 60 via a wire70. Then, an electrode of the LED chip 60 is connected to an electrodeof an adjacent LED chip 60 via a wire 70. Subsequently, the rest of theLED chips 60 in the first area 110 are similarly connected in turn toeach other via wires 70. An electrode of the 21st LED chip 60 isconnected to the bridge electrode 99 via a wire 70, and the bridgeelectrode 99 is connected to an electrode of one of the LED chips 60 inthe second area 120. With the configuration, the LED chips 60 in thefirst area 110 and the LED chip 60 in the second area 120 are connectedto each other via the bridge electrode 99. Then, the LED chips 60 in thesecond area 120 are connected to each other in turn via wires 70.Lastly, an electrode of the 6th LED chip 60 is connected to an end partof an electrode land 90 via a wire 70. Accordingly, the electrode land95 and the electrode land 90 are connected in series via the LED chips60 and the bridge electrode 99.

(Method for Producing Light-Emitting Device 450)

A method for producing the light-emitting device 450 of the presentembodiment is the same as the production method of Embodiment 1.

(First Measurement)

After the first fluorescent-substance-containing resin layer 40 isprovided, the first measurement of a chromatic characteristic of thelight-emitting device 450 is carried out by, for example, causing the 21pieces of the LED chips 60 provided in the first area 110 and 6 piecesof the LED chips 60 provided in the second area 120 to emit light.

(Second Measurement)

Then, after the second fluorescent-substance-containing resin layer 50is provided in the second area 120, the chromatic characteristic of thelight-emitting device 450 is measured. The second measurement is carriedout by, for example, causing the 21 pieces of the LED chips 60 providedin the first area 110 and the 6 pieces of the LED chips 60 provided inthe second area 120 to emit light.

In the light-emitting device of the present invention, it is preferablethat the partition wall (i) is formed on the substrate in such a mannerthat the partition wall has a circular shape or a cyclic polygonal shapewhen the substrate is viewed from above and (ii) includes at least twopartition walls which are formed concentrically.

According to the configuration, it is possible to provide thelight-emitting devices among which unevenness of chromaticities thereofis reduced. The light-emitting device can be suitably used, for example,as a light source of an illuminating device having a circular shape withrespect to its light emitting face, or as a light source of anilluminating device which needs to be optically connected with anexternal optical component appropriately. The illuminating device havinga circular shape with respect to its light emitting face can be, forexample, a bulb-type illuminating device. The illuminating device whichneeds to be optically connected with an external optical componentappropriately can be, for example, an illuminating device which isprovided with an external lens for adjusting a light distributioncharacteristic which external lens is provided directly above theilluminating device.

In the light-emitting device of the present invention, it is preferablethat the plurality of light-emitting elements are provided along acircle which is concentric with the partition wall.

According to the configuration, it is possible to provide thelight-emitting devices among which unevenness of chromaticities thereofis reduced. The light-emitting device can be suitably used, for example,as a light source of an illuminating device having a circular shape withrespect to its light emitting face, or as a light source of anilluminating device which needs to be optically connected with anexternal optical component appropriately. The illuminating device havinga circular shape with respect to its light emitting face can be, forexample, a bulb-type illuminating device. The illuminating device whichneeds to be optically connected with an external optical componentappropriately can be, for example, an illuminating device which isprovided with an external lens for adjusting a light distributioncharacteristic which external lens is provided directly above theilluminating device.

In the light-emitting device of the present invention, it is preferablethat the sealing material in each of the plurality of areas is differentin at least one of fluorescent substance content and fluorescentsubstance composition.

According to the configuration, it is possible that one of the sealingmaterials is provided in a certain area and a chromaticity is measured,and then an amount and a composition of a fluorescent substancecontained in the other sealing material to be provided in the other areacan be determined based on the measurement result. This makes itpossible to provide the light-emitting devices among which unevenness ofchromaticities thereof is reduced.

In the light-emitting device of the present invention, it is preferablethat the sealing material contains plural kinds of fluorescentsubstances.

According to the configuration, it is possible to provide thelight-emitting device which includes a plurality of fluorescentsubstances and accordingly capable of emitting light of a substantiallydesired color.

In the light-emitting device of the present invention, it is preferablethat the partition wall is colored with milky white or white.

According to the configuration, it is possible to prevent the partitionwall from absorbing light emitted by the plurality of light-emittingelements. This makes it possible to prevent the partition wall fromweakening the light emitted by the plurality of light-emitting elements.

In the light-emitting device of the present invention, it is preferablethat the plurality of light-emitting elements are separated into aplurality of groups in which light-emitting elements in a same group areconnected to each other via a patterned wire(s).

According to the configuration, turning on or off of the plurality oflight-emitting elements can be controlled for each of the plurality ofgroups. This makes it possible to measure more detailed chromaticcharacteristics of the light-emitting devices, and accordinglyunevenness among the chromaticities can be reduced.

It is preferable that the light-emitting device of the present inventionfurther includes at least one of a protective element and a printedresistor, between a main surface of the substrate and the partitionwall.

According to the configuration, at least one of the protective elementand the printed resistor is provided between the main surface of thesubstrate and the partition wall. This makes it possible to (i) reducean amount of light, which is emitted by the light-emitting element,absorbed by at least one of the protective element and the printedresistor and (ii) protect a surface of at least one of the protectiveelement and the printed resistor.

In the light-emitting device of the present invention, it is preferablethat the at least one of the protective element and the printed resistoris wholly covered with the partition wall.

According to the configuration, at least one of the protective elementand the printed resistor is wholly covered with the partition wall. Thismakes it possible to (i) reduce an amount of light, which is emitted bythe light-emitting element, absorbed by at least one of the protectiveelement and the printed resistor and (ii) protect a surface of at leastone of the protective element and the printed resistor.

In the light-emitting device of the present invention, it is preferablethat the substrate is further provided with a first electrode land forexternal connection and a second electrode land for external connectionwhich (i) are respectively provided on both end areas of the mainsurface of the substrate and (ii) are not covered with the sealingmaterial.

According to the configuration, a conductive wire can be easily anddirectly connected to the electrode land with the use of, for example,solder.

In the light-emitting device of the present invention, it is preferablethat the substrate is provided with a bridge electrode with which one ofthe plurality of light-emitting elements embedded in a first area isconnected to another one of the plurality of light-emitting elementsembedded in a second area, the first area and the second area beingareas among the plurality of areas.

According to the configuration, the light-emitting elements embedded inrespectively different areas can be connected to each other.

In the light-emitting device of the present invention, it is preferablethat the bridge electrode is provided between the substrate and thepartition wall and traverses the partition wall.

According to the configuration, it does not need to newly prepare aspace for providing the bridge electrode. This makes it possible toprovide the light-emitting device whose size is not enlarged forproviding the bridge electrode.

In the light-emitting device of the present invention, it is preferablethat a part of the bridge electrode which part traverses the partitionwall is thinner than the other part of the bridge electrode.

According to the configuration, in the part where the bridge electrodetraverses the partition wall, it is possible to shorten a distancebetween the partition wall and the substrate which distance is occurreddue to a thickness of the bridge electrode. This makes it possible toprovide the light-emitting device which can prevent a problem that thesealing materials are not separated into each of the areas andaccordingly mixed together, since the bridge electrode is provided.

In the light-emitting device of the present invention, it is preferablethat the plurality of light-emitting elements are connected in seriesvia the bridge electrode.

According to the configuration, an area of a metal surface is not smallon the substrate. This makes it possible to provide the light-emittingdevice in which (i) reflection ratio of light emitted from thelight-emitting elements is improved, (ii) deterioration of the metalsurface is reduced, and (iii) adhesivity between the sealing materialand the substrate is improved.

In the light-emitting device of the present invention, it is preferablethat the partition wall contains at least one of a thickener and adiffusing agent.

According to the configuration, it is possible to give lightreflectivity to the partition wall and to prevent the partition wallfrom absorbing light emitted from the plurality of light-emittingelements. This makes it possible to provide the light-emitting devicewhich can prevent the partition wall from weakening the light emitted bythe plurality of light-emitting elements.

In the method for producing the light-emitting device of the presentinvention, it is preferable that the step (a) includes (g) providing,before the step (d), some of the plurality of light-emitting elements inone of the areas separated by the partition wall, and (h) providing,after the step (d), rest of the plurality of light-emitting elements inthe other one of the areas in which the second sealing material is to beformed.

According to the configuration, a chromatic characteristic of thelight-emitting device in which the first sealing material has beenprovided can be measured regardless of light-emission by the pluralityof light-emitting elements provided in the other one of the areas inwhich the second sealing material is to be formed. This makes itpossible to carry out more detailed measurement of the chromaticcharacteristic of the light-emitting device in which the first sealingmaterial has been formed.

It is preferable that the method for producing the light-emitting deviceof the present invention further includes the step of (i) providing,before the step (d), a light-shielding plate in such a manner that thelight-shielding plate covers the second sealing material.

According to the configuration, a chromatic characteristic of thelight-emitting device in which the first sealing material has beenprovided can be measured regardless of light-emission by the pluralityof light-emitting elements provided in the other one of the areas inwhich the second sealing material is to be formed. This makes itpossible to carry out more detailed measurement of the chromaticcharacteristic of the light-emitting device in which the first sealingmaterial has been formed.

It is preferable that the method for producing the light-emitting deviceof the present invention includes the steps of: (j) providing, insteadof the step (e), a pseudo fluorescent sheet so that the pseudofluorescent sheet covers the other one of the areas in which the secondsealing material is to be formed; and (k) measuring a chromaticcharacteristic of the light-emitting device in which the pseudofluorescent sheet has been provided.

According to the configuration, it is possible to measure the chromaticcharacteristic of the light-emitting device without providing the secondsealing material. Accordingly, it is possible that the pseudofluorescent sheet is selected so that a desired chromaticity can beobtained and the second sealing material is formed in accordance withthe pseudo fluorescent sheet. This provides an effect of easilyproducing the light-emitting devices among which unevenness ofchromaticities thereof is reduced.

The present invention is not limited to the description of theembodiments above, but can be altered by a skilled person in the artwithin the scope of the claims. An embodiment derived from a propercombination of technical means disclosed in respective differentembodiments is also encompassed in the technical scope of the presentinvention.

INDUSTRIAL APPLICABILITY

The light-emitting device of the present invention and the method forproducing the light-emitting device can be suitably applied to a lightsource of an illuminating device, a light source of a backlight of aliquid crystal display, or the like.

REFERENCE SIGNS LIST

-   10 and 12: Ceramic substrate (substrate)-   15: Patterned electrode wire-   16: First electric area-   17: Second electric area-   18: Third electric area-   20: First resin ring (partition wall)-   30: Second resin ring (partition wall)-   40: First fluorescent-substance-containing resin layer (sealing    material, first sealing material)-   50: Second fluorescent-substance-containing resin layer (sealing    material, second sealing material)-   60: LED chip-   70: Wire-   80 and 85: Printed resistance element-   90: Electrode land (anode) (first electrode land for external    connection)-   95: Electrode land (cathode) (second electrode land for external    connection)-   97: Hole for mounting a substrate-   99: Bridge electrode-   100, 200, 250, 300, 400, and 450: Light-emitting device-   110: First area (area)-   120: Second area (area)-   310: Light-shielding plate-   350: Pseudo fluorescent sheet-   510: Base substrate-   520: LED chip

What is claimed is:
 1. A light-emitting device comprising: a pluralityof light-emitting elements and a patterned electrode wire provided on asubstrate; and a sealing material in which the plurality oflight-emitting elements are embedded, wherein: some of the plurality oflight-emitting elements are electrically connected to the patternedelectrode wire via wires, the sealing material being divided into aplurality of areas by a partition wall, and the patterned electrode wireand the wires are partially covered with the partition wall.
 2. Thelight-emitting device as set forth in claim 1, wherein: each of theplurality of areas is a continuous area which is not divided intosmaller segments.
 3. The light-emitting device as set forth in claim 1,wherein: the partition wall has a circular shape or a cyclic polygonalshape when the substrate is viewed from above.
 4. The light-emittingdevice as set forth in claim 3, wherein: the partition wall includes atleast two partition walls which are formed concentrically.
 5. Thelight-emitting device as set forth in claim 4, wherein: the plurality oflight-emitting elements are provided along a circle which is concentricwith the partition wall.
 6. The light-emitting device as set forth inclaim 1, wherein: the sealing material in each of the plurality of areasis different in at least one of fluorescent substance content andfluorescent substance composition.
 7. The light-emitting device as setforth in claim 1, wherein: the sealing material contains plural kinds offluorescent substances.
 8. The light-emitting device as set forth inclaim 1, wherein: the partition wall is colored with milky white orwhite.
 9. The light-emitting device as set forth in claim 1, wherein:the plurality of light-emitting elements are separated into a pluralityof groups in which light-emitting elements in a same group are connectedto each other via a patterned electrode wire(s) each of which is saidpatterned electrode wire.
 10. The light-emitting device as set forth inclaim 1, further comprising: at least one of a protective element and aprinted resistor, between a main surface of the substrate and thepartition wall.
 11. The light-emitting device as set forth in claim 10,wherein: the at least one of the protective element and the printedresistor is wholly covered with the partition wall.
 12. Thelight-emitting device as set forth in claim 1, wherein: the substrate isfurther provided with a first electrode land for external connection anda second electrode land for external connection which (i) arerespectively provided on both end areas of the substrate and (ii) arenot covered with the sealing material.
 13. The light-emitting device asset forth in claim 1, wherein: the substrate is provided with a bridgeelectrode with which one of the plurality of light-emitting elementsembedded in a first area is connected to another one of the plurality oflight-emitting elements embedded in a second area, the first area andthe second area being areas among the plurality of areas.
 14. Thelight-emitting device as set forth in claim 13, wherein: the bridgeelectrode is provided between the substrate and the partition wall andtraverses the partition wall.
 15. The light-emitting device as set forthin claim 13, wherein: the plurality of light-emitting elements areconnected in series via the bridge electrode.
 16. The light-emittingdevice as set forth in claim 1, wherein: the partition wall contains atleast one of a thickener and a diffusing agent.